Radiator Cap Relief Pressure May Be Too High Caterpillar

Radiator Cap Relief Pressure May Be Too High

Usage:

ARTICULATED TRUCKSD20D (9MG1-UP),
D250D (6NG1-UP) ARTICULATED TRUCKS

Problem:

The relief pressure on some of the 6U-2421 Radiator Caps used on the D20D and D250D Articulated Trucks may be too high. The correct relief pressure for the 6U-2421 Radiator Cap is 7 psi.

Solution:

At the first opportunity, check the 6U-2421 Radiator Cap using the following method.

1. Relieve any pressure that may be present in the cooling system.

2.Remove the 2B-7409 Plug (Item 15 in the illustration) from the 2U-6448 Tank.

3.Connect a 9S-8140 Cooling System Pressurizing Pump to the header tank.

4.Pressurize the header tank and observe the pressure at which the radiator cap opens. The pressure should be relieved at 7 psi.

5.If the pressure is relieved at a pressure higher than 7 psi, install a new 6U-2421 Radiator Cap.

NOTE: Check the relief pressure of the new 6U-2421 Radiator Cap before putting the machine in service.

Caterpillar Information System:

Instructions To Eliminate Water Leaking From Roof Air Conditioner Into Cab Instructions To Eliminate Water Leaking From Roof Air Conditioner Into Cab

Possible Failure Of 8X-5972 Steering Hose Due To Chafing On Sevice Brake Clip Possible Failure Of 8X-5972 Steering Hose Due To Chafing On Sevice Brake Clip

Front Upper Cylinder Bearing Cap Bolts May Be Too Long Front Upper Cylinder Bearing Cap Bolts May Be Too Long

Blowby Measurement For the Above Turbocharged Engines Blowby Measurement For the Above Turbocharged Engines

Seals Can Be Damaged When Removing Or Installing The Cut-Out Cartridge Valve From The Body Of The Accumulator Charging Valve Group Seals Can Be Damaged When Removing Or Installing The Cut-Out Cartridge Valve From The Body Of The Accumulator Charging Valve Group

Improved Shift Handle Requires Special Installation Procedure Improved Shift Handle Requires Special Installation Procedure

Unnecessary Replacement Of Hand Metering Units Unnecessary Replacement Of Hand Metering Units

Seat Tethers Field Information Seat Tethers Field Information

Front Suspension Cylinder Head Bolts Cannot Be Tightened Correctly If Too Much Silicone Sealant Is Used During Assembly Front Suspension Cylinder Head Bolts Cannot Be Tightened Correctly If Too Much Silicone Sealant Is Used During Assembly

Possible Interference Between The Lockup Clutch Hub Retaining Bolts And The Thrust Bearing Race Possible Interference Between The Lockup Clutch Hub Retaining Bolts And The Thrust Bearing Race

Implement Valve Signal Line May Crack And Leak Due To Vibration Implement Valve Signal Line May Crack And Leak Due To Vibration

Retaining Bolts That Hold The Fan Spider Assembly May Come Loose Retaining Bolts That Hold The Fan Spider Assembly May Come Loose

9J-4693 Brake Accumulator Charging Valve 9J-4693 Brake Accumulator Charging Valve

Cooling System Overheating Cooling System Overheating

Noise In Hydraulic System Noise In Hydraulic System

Slide Frame Locking Plate Slide Frame Locking Plate

Transmission Oil Filter Failures Transmission Oil Filter Failures

Use Of "ARCTIC REGION" Suspension Cylinder Seals In Temperate Climate Applications Use Of "ARCTIC REGION" Suspension Cylinder Seals In Temperate Climate Applications

Oil Leakage From 8R8529 Control Group Brake Oil Leakage From 8R8529 Control Group Brake

Improved Coolant Now Factory Filled Improved Coolant Now Factory Filled

Bolts That Hold the 9D-2863 Adapters To The Hydraulic Tank May Not Be Correct Bolts That Hold the 9D-2863 Adapters To The Hydraulic Tank May Not Be Correct

Air Conditioner Thermostatic Switch May Fail If The 105-8827 Suppressor (Diode) In The Air Conditioner Circuit Is Bypassed Or Removed Air Conditioner Thermostatic Switch May Fail If The 105-8827 Suppressor (Diode) In The Air Conditioner Circuit Is Bypassed Or Removed

Front Axle Mounting Bolts Front Axle Mounting Bolts

Lower Side-Plate Bolts Coming Loose Lower Side-Plate Bolts Coming Loose